I've never set off a smoke detector by vaping, but I sure have seen it happen at a vape convention where every other guy seemed to be in a one-man cloud competition. My house is heavily alarmed (both photocell and ionization smoke detectors, plus CO detectors), and we have set them off by cooking, steam, and letting the popcorn popper go a bit past optimum. We have also had what seem to be false alarms, which were probably caused by over-aged detectors. But never by vaping - home or hotel. To be fair, I vape at low wattages (8-10 Watts) and fairly low VG (68/32 PG/VG), so I don't tend to generate a lot of visible vapor.

Smoke alarms only have a lifespan of about 10 years. Then it's time to replace your home smoke detectors - for your own safety as much as to avoid false alarms. For CO (carbon monoxide) detectors the lifespan is even shorter - replace after 5 years to be on the safe side. (All three types seem to get more sensitive as they age - unless they totally fail and become completely insensitive.) Not much you can do about hotel detectors except don't stay at El-Cheapo Inn where they put off replacing them as long as possible.

You can never tell with smoke detectors these days. Many, these days will be set off by vaping as the particulates will set off the sensor.

So I do one of two things:

1 - Vape in the room only if there is a window, or something of the sort, that leads directly to the outside. Blow the cloud outside.

2 - Vape in the bathroom. Bathrooms with showers will not have a particularly sensitive smoke detectors as the steam from a hot shower could set them off. If the bathroom has no exhaust fan, make sure the door is closed when you exit as well otherwise it may set off more sensitive detectors in the main room.